Fülöp Éva – Cseh Julianna szerk.: „Die aktuellen Fragen des Mittelpaläolithikums in Mitteleuropa”. „Topical issues of the research of Middle Palaeolithic period in Central Europe”. Tata, 20-23 October 2003. (Tudományos Füzetek 12. Tata, 2004)

Sándor Kele–László Korpás–Péter Kovács-Pálffy–Miklós Lantos: Sedimentology, mineralogy, lake evolution and chronology of the Quaternary Tata thermal lacustrine travertine

Introduction (and geological background) During the Late Miocene and Holocene intensive spring activity characterized the W-Gerecse Mts, and as a result of this in the surroundings of Tata many local travertine deposits were formed (Fig. i).

1 The Porhanyó-Quarry (Fig, 2) is situated in the neighbourhood of the Eötvös Secondary School (Tata), on the west side of the Oreg-lake, and was named after its loose, friable sediment. The quarry became famous from its archaeological finds. The limestone occuring in the quarry deposited from the parents of the springs, which once fed the Fényes- and Cseke-lake (Tata). The karst-springs discharged from Mesozoic carbonates on the alluvium of the Altai-creek, on the Il/a

—and sometimes on the Il/b

—terraces (Népkert-springs).

2 The freshwater limestones deposited from the Fényes-springs on the alluvium of the Altai-creek together with limestones occuring on the west-side and east-side of the Oreg-lake (on the Il/a terrace). The rocks are porous, friable and dissected by mud- and sand-layers. The layers are drab, pale yellow and their thickness is 1-2 m. The freshwater limestones located on the 11/ b terrace of the Altai-creek belong to the marsh-pool facies type but comprise also tetaratas, which indicate smooth-slope facies. Similar travertines can be found on the eastern part of the Oreg-lake until the Cseke-lake (in the area of Tata town). The layers settled here comprising tetaratas deposited from the "Angolkert-springs" (Népkert-springs) when the springwater flew into the Altai-creek that was located at a deeper position.

3 After Scheuer and Schweitzer and Pécsi the travertines of the Porhanyó-quarry were deposited on the terrace Il/a and Il/b of the Altai-creek as a tetarata-pool system.

4 The height of this terrace is 146 m asl. and it is 15-20 m above the present valley floor.

5 According to Pécsi (1959) the formation of this terrace level took place around the end of the penultimate (Riss) or the beginning of last (wiirm) glaciation. The terrace is covered by the T2 travertine horizon of 5-8 m thickness.

6 The first palynological investigation of Tata-Porhanyóbánya was carried out in 1958, A 19 m long core was drilled into the travertine, the samples were analyzed at every 20 cm

7 and 19 pollen taxa were identified. In May 2003 new pollen analytical research started at the locality. 1 SCHAFARZIK I9O4.; DOBOSI 2003, 205-214.; LENKEI I943, II5-II7.; HoRUSITZKY 1923.; SCHRÉTER 1951, m-150.; VÉRTES ET AL. 1964.; SCHEUER-SCHWEITZER 1974, 113-134.; SCHEUER-SCHWEITZER 1988,131. 2 SCHEUER-SCHWEITZER 1988,131. 3 SCHEUER-SCHWEITZER I988, 131. 4 SCHEUER-SCHWEITZER 1988, I3I.; PÉCSI 1959, 34-6. 5 RUSZKICZAY-RÜDRIGER 2OO3. 6 SCHWEITZER-SCHEUER 1995,163-186. 7 JÁRAI-KOMLÓDI I964, 67-77. 34